PRIOR CONCURRENT THERAPY: Biologic therapy: At least 5 days since prior immunotherapy Chemotherapy: At least 3 weeks since prior chemotherapy (6 weeks for nitrosoureas and similar compounds) No more than 3 prior chemotherapy regimens for metastatic disease No prior anthracycline exposure exceeding 300 mg/m2 doxorubicin No prior doxorubicin HCl liposome Endocrine therapy: At least 5 days since prior hormonal therapy Radiotherapy: At least 3 weeks since prior radiotherapy and recovered No prior radiotherapy to more than 30% of functioning bone marrow Surgery: At least 3 weeks since prior major surgery Other: No other concurrent experimental drugs No other concurrent anticancer therapy